1. Field of the Invention
This invention relates to user administration in a mobile communication system, and in particular to reconciling duplicate Personal Identification Number (PIN) registrations, i.e. the same device PIN being used by more than one user.
2. Description of the Prior Art
Personal Identification Numbers (PINs) are used to identify a wireless mobile communications device within a communication network, hereinafter referred to primarily as a “mobile device”. The registration of the mobile device in the communication network effectively associates the particular mobile device with a particular user messaging account.
In prior art communication systems, two user accounts with the same PIN could potentially be created within the same system. This could happen, for example, when a new user takes over a mobile device previously used by another user. When the mobile device PIN is associated with an account for the new user, but also remains associated with the previous user's account, this results in communications for the two different user accounts, such as host system mailboxes for example, being sent to a single mobile device, and vice versa. In a messaging system, network resources are therefore expended to deliver messages intended for one user's account to a different user's mobile device. For the intended recipient, this represents a substantial security issue, since another user may be receiving his or her messages. Furthermore, for the mobile device user, increased message traffic due to messages for the other user account consumes mobile device power and resources, thus shortening battery life, and may also increase airtime costs.
When operating within a secure system, a mobile device and a host system which communicates with the mobile device sometimes use corresponding encryption keys in order for decryption of secure communications to occur successfully. Therefore, in the above example of a mobile device PIN being associated with two user accounts, associated although messages for both user accounts would be sent to the mobile device, messages for only one of the user accounts could be successfully decrypted at the mobile device. Since over-the-air protocols do not typically identify a user or user account, a host system would be unable to determine, using the device PIN, which user's account should be associated with the PIN. If the wrong account is chosen, then the associated encryption key will be used to encrypt a message, and attempts to decrypt messages at the mobile device would fail. Similarly, incoming message from a mobile device whose PIN has been associated with more than one user account might not be properly decrypted at a host system when an incorrect one of the user accounts is chosen.
Therefore, there remains a need for a system and method for detecting duplicate mobile device PIN assignments and reconciling such conflicting mobile device registrations.